The invention relates to a roller press for the pressure treatment of granulated material, particularly for the comminuting, compacting or briquetting of a bed of granular material, said press having two rollers, which are rotatably mounted in bearing housings, driven in a contrarotating manner and are separated from each other by a roller nip, the bottom sides and top sides of the bearing housings being mounted on sliding tracks of brackets of the machine frame, using hydraulic cylinders to press the one roller against the oppositely situated roller over the material situated in the roller nip.
In roller grinding to carry out the so-called material bed comminution, the individual pieces or particles of the material to be ground, drawn into the roller nip through friction, such as, for example, raw cement material, cement clinker, ore or the like, are pressed and mutually comminuted at a high pressure in a material bed, that is to say in a material fill compacted between the surfaces of the two rollers, also referred to as a roller press or roll press instead of a roll mill. In the case of such known roller presses, see, for example, the brochure entitled “Rollenpressen” (Roller presses), No. 2-300d of KHD Humboldt Wedag AG dated September 1994 or, for example, WO 2005/070549 A1, one of the two rollers is designed in the form of a fixed roller which is supported via its bearing housing against end pieces of the machine frame, whilst the other roller, in the form of a loose roller, is supported via its bearing housing by hydraulic cylinders, by means of which the roller compaction force is applied.
During the operation of these types of roller presses, the surfaces of the rollers are exposed to a high level of wear and tear due to the high compacting pressures and pressing forces, especially when the loose roller, depending on the material supply to the roller nip, makes side deflecting movements, the central position of the roller nip and of the pressed material slug emerging downwards from said roller nip then altering due to the on the roller surface. Apart from the enormous dead weight provided by the heavily weighted rollers, a shock-like change in the roller nip width, for example caused by a foreign body going through the double rocker roller mill, is an additional strain on the rocker mounting pivot joints, which consequently have to be designed to be especially sturdy and weighty.